<meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1"></script>
<style>h1{margin-top:5%;margin-bottom:5%;}body{ text-align:center;} table{width: 100%;height: 100%;margin: 5% auto;}
@media (max-width: 500px){h1{margin-top:10%;margin-bottom:10%;}body{ text-align:center;} 
table{width: 100%;height: 100%;margin: 20% auto;}}</style></head>
<body background="http://pic1.win4000.com/mobile/9/59701ad479f6a.jpg">
<h1>ESP32文件管理</h1>
<dev> <input id="newfile" type="file" style="width:50%;"><button id="upload" type="button" onclick="upload()" >上传</button>
</dev>
<script>
var filePath;
function upload() {
var filePath = document.getElementById("newfile").files[0].name;
var upload_path = "/upload/" + filePath;
var fileInput = document.getElementById("newfile").files;
var MAX_FILE_SIZE = 200*1024;
var MAX_FILE_SIZE_STR = "200KB";
if (fileInput.length == 0) {
    alert("No file selected!");
    } else if (filePath.length == 0) {
        alert("File path on server is not set!");
    } else if (filePath.indexOf(' ') >= 0) {
        alert("File path on server cannot have spaces!");
    } else if (filePath[filePath.length-1] == '/') {
        alert("File name not specified after path!");
    } else if (fileInput[0].size > 300*1024) {
        alert("File size must be less than 300KB!");
    } else {
        document.getElementById("newfile").disabled = true;
        document.getElementById("upload").disabled = true;
        var file = fileInput[0];
        var xhttp = new XMLHttpRequest();
        xhttp.onreadystatechange = function() {
        if (xhttp.readyState == 4) {
            if (xhttp.status == 200) {
                document.open();document.write(xhttp.responseText);document.close();
            }else if (xhttp.status == 0) {
                alert("Server closed the connection abruptly!");
                location.reload()
                } else {alert(xhttp.status + " Error!\n" + xhttp.responseText);location.reload()}}
        };
        xhttp.open("POST", upload_path, true);xhttp.send(file);
}}</script>